A 58-year-old man from Delhi presents to the emergency department with chest pain of 3 hours duration. The pain is substernal, radiating to the left arm, and associated with diaphoresis. He has a history of hypertension and type 2 diabetes. Vital signs: BP 128/82 mmHg, HR 92 bpm, RR 18/min. Physical examination is unremarkable. 12-lead ECG shows ST depression of 2 mm in leads II, III, and aVF with T-wave inversion in the same leads. Troponin I is 0.8 ng/mL (normal <0.04). What is the most appropriate next step in management?

Explanation

## Clinical Diagnosis This patient presents with **NSTEMI** (Non-ST-Elevation Myocardial Infarction): - Chest pain consistent with acute coronary syndrome (ACS) - ST depression and T-wave inversion in inferior leads (reciprocal changes suggesting inferior wall ischemia) - Elevated troponin I (0.8 ng/mL) confirming myocardial necrosis ## Risk Stratification **Key Point:** This patient has **high-risk features** for NSTEMI: - Elevated cardiac biomarkers (troponin positive) - Dynamic ST-segment changes (depression + T-wave inversion) - Ongoing symptoms at presentation ## Management Strategy **High-Yield:** According to ACC/AHA and ESC guidelines, **all patients with NSTEMI should undergo early invasive strategy** (coronary angiography within 24 hours, ideally within 12 hours for high-risk patients). ### Dual Antiplatelet Therapy (DAPT) | Agent | Loading Dose | Mechanism | |-------|--------------|----------| | Aspirin | 325 mg (or 300–600 mg) | COX inhibitor, irreversible platelet inhibition | | Clopidogrel | 600 mg | P2Y12 inhibitor (ADP receptor antagonist) | | Ticagrelor | 180 mg | P2Y12 inhibitor (faster onset than clopidogrel) | **Clinical Pearl:** Clopidogrel 600 mg loading dose is standard in NSTEMI. Ticagrelor 180 mg is an alternative with faster onset but is not the first choice in this scenario given the clinical context. ### Immediate Coronary Angiography **Key Point:** Early invasive strategy (coronary angiography ± PCI) is the standard of care for NSTEMI, particularly in high-risk patients. This allows: 1. Identification of culprit lesion 2. Assessment of collateral circulation 3. Revascularization (PCI or CABG) if indicated 4. Risk stratification based on angiographic findings **Mnemonic: NSTEMI Management = DAPT + Early Angiography** - **D**ual antiplatelet therapy (aspirin + P2Y12 inhibitor) - **A**nticoagulation (unfractionated heparin or LMWH) - **P**erfusion strategy (early invasive) - **T**roponin-positive (confirms myocardial necrosis) ## Why Option 0 is Correct Immediate dual antiplatelet therapy (aspirin + clopidogrel 600 mg loading dose) combined with **immediate coronary angiography** is the guideline-recommended approach for high-risk NSTEMI. This patient meets criteria for early invasive strategy due to elevated troponin and dynamic ST changes.